Embodiments herein generally relate to printing devices that utilize charging devices and patterning devices that pattern the charge on a photoreceptor, and more particularly to embodiments that include a dual function cleaner that simultaneously cleans both the charging elements and the patterning elements.
Electrostatic printing devices generally create a uniform charge on a photoreceptor using charging devices such as a corona charging device or a scorotron charging device and then patterned that charge using a patterning device (which can comprise, for example, a laser based raster output scanner (ROS)). The charging device needs to be cleaned on a regular basis and, therefore, auto-cleaning devices for the corona or scorotron devices have been developed. See for example, U.S. Patent Publication Number 2008/0069586, the complete disclosure of which is incorporated herein by reference.
However, improved printing quality can also be achieved by periodically cleaning the patterning devices (ROS). However, such cleaning processes are manually performed and are therefore expensive, sometimes performed inconsistently, and sometimes not performed when needed. Therefore, the embodiments described below provide a device and method whereby the patterning devices are cleaned each time the charging devices are cleaned, and such embodiments utilizes a single device to perform both operations, thereby decreasing costs and increasing reliability. By consistently cleaning the latent image patterning devices, the image quality consistently remains at a high level.
One generalized embodiment herein is a printing apparatus that includes a charging device and a photoreceptor adjacent the charging device. The charging device transfers a charge to the photoreceptor. Also, a charge patterning device is adjacent the photoreceptor. The patterning device patterns the charge on the photoreceptor to form a latent image charge.
A marking material donor device is adjacent the photoreceptor. The marking material donor device transfers marking material to areas of the photoreceptor having the latent image charge, such that the marking material is patterned into an image pattern according to the latent image charge on the photoreceptor. A sheet transport device is adjacent the photoreceptor. The sheet transport device supplies at least one sheet of media to the photoreceptor. The photoreceptor transfers the marking material to the sheet of media in the image pattern. A heating device is adjacent the photoreceptor, the heating device permanently attaches the marking material to the sheet of media in the image pattern.
Additionally, an automated cleaning device is adjacent the charging device. The charge patterning device periodically moves by the charging device and the charge patterning device to simultaneously clean the charging device and the charge patterning device.
Another more specific embodiment herein is a printing apparatus that utilizes a corona, corotron, or scorotron charging device, and a photoreceptor adjacent the corona charging device. The charging device transfers a charge to the photoreceptor. Further, a raster output scanner (ROS) is adjacent the photoreceptor. The raster output scanner patterns the charge on the photoreceptor to form a latent image charge.
A marking material donor roll is adjacent the photoreceptor, the marking material donor roll transfers marking material to areas of the photoreceptor having the latent image charge, such that the marking material is patterned into an image pattern according to the latent image charge on the photoreceptor.
Also, a sheet transport device is adjacent the photoreceptor, the sheet transport device supplies at least one sheet of media to the photoreceptor. The photoreceptor transfers the marking material to the sheet of media in the image pattern. A fuser is adjacent the photoreceptor, and the fuser permanently attaches the marking material to the sheet of media in the image pattern.
Again, an automated cleaning device is adjacent the charging device and the raster output scanner. The automated cleaning device periodically moves by the charging device and the raster output scanner to simultaneously clean the corona charging device and the raster output scanner. The printing apparatus produces debris from the sheet of media and the marking material, that collects on the raster output scanner, the cleaning device removes the debris from the raster output scanner.
In one embodiment, the automated cleaning device comprises a brush that is positioned to pass over the raster output scanner as the automatic cleaning device moves by the charging device. More specifically, the raster output scanner has an outer covering and the brush has a shape and size that matches the outer covering of the raster output scanner. In another embodiment, the brush can comprise a rotating fibrous surface having fibers sized to catch and hold the debris.
With printing devices according to embodiments herein, the charging device and the raster output scanner are positioned in sufficiently close proximity to one another to allow the automated cleaning device to simultaneously clean the charging device and the raster output scanner.
These and other features are described in, or are apparent from, the following detailed description.